Melanocortin 1 receptor (MC1R) is highly expressed on uveal and cutaneous melanoma cells and not on any tissues that are of concern for causing toxicity. We developed a proprietary ligand (MC1RL) that binds to melanoma cells with high affinity and specificity. Our recently completed SBIR Phase I contract results show no overt toxicity at dosages of Ac-225-DOTA-Ahx-MC1RL that produce outstanding efficacy against uveal and cutaneous melanoma in animal models. Biodistribution, radiodosimetry, and PK studies also show rapid blood clearance with predominant distribution to the targeted tumor or to clearance organs with no organ specific pathology. These results are very supportive of possible commercialization of a human drug candidate for the treatment of metastatic melanoma.